Company Switch Tie-in

First of all, I am a student, and am NOT interested in doing any of this work myself.

Our venue has two company switches SR, one 400A, the other 150A. They are both 3 phase, and both have cam lock connectors.

For several rock concert-style shows we do, we simply run out of outlets for the onstage sound gear. I noticed that one show that came through (Up With People) used the bigger company switch to power their dimmer rack. So, I was wondering why we couldn't use the smaller one to power audio gear.

I do understand that anything connected to these switches would need to have it's own individual circuit protection. My question is this: Is there a type of distro made that is safe to use for this purpose for onstage audio equipment? Assume that there is a licensed electrician performing all connections and that all district regulations are followed. I only want to know if they make a distro suitable for this, I'm not asking how to do it because I would not be the one working with the tie-in.
 
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Thank you very much, Trevor and Derek, those are EXACTLY what I was thinking of.

Because this is in a school, do you think that going to the school electrician is the right way to go about getting one of these hooked up? (It would only be about three times a year)
 
Depending on your space available, it should be fine just to leave a distro hooked up and just flip the switch off when it isn't needed. I'm not entirely sure of what students or faculty are allowed to do and aren't allowed to do where you are, but it's also possible to leave the tails attached to the company switch and just patch them into the distro as needed, Leaving the company switch off at all times it's not in use just in case. It really isn't like you are modifying building wiring, you are only (well, essentially) plugging something in. It's just something that could kill you quite a bit easier if you mess around with it.
 
That's exactly what I thought, having read up on some old threads about tie-ins. Thanks Marshall! The smaller switch has a padlock on the lever, so leaving it connected may work. I'll check with the electrician tomorrow.
 
... Because this is in a school, do you think that going to the school electrician is the right way to go about getting one of these hooked up? ...
Not necessarily. The use of single-pole separable connectors (Cam-Lok s) is limited to use by a Qualified Person, per the NEC (see definition below) . This might be the school electrician, but could also include: a state-licensed electrician, an IBEW member, an ETCP-Certified Entertainment Electrician, the venue TD, or even a student WITH THE PROPER TRAINING.

Qualified Person. One who has skills and knowledge related to the construction and operation of the electrical equipment and installations and has received safety training to recognize and avoid the hazards involved.
It's very possible that your school electrician has never seen or used a Cam-Lok connector, and thus WOULD NOT be a Qualified Person, per the NEC.

... The smaller switch has a padlock on the lever, so leaving it connected may work. ...
There's your answer. You need to go to whomever controls the key to the padlock.

Be aware that even the smallest of distro s is not inexpensive. Since you only anticipate using it three times a year, it may be more economical to rent (from your local lighting, audio, or A/V company--just ask for an "Edison distro.") rather than purchase. A 10' set (of five) 2/0 Cam-Lok cables could cost ~$500, plus the distro (Lex Pagoda 15x20A) ~$1200. A one week rental is likely less than $100.
 
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There's your answer. You need to go to whomever controls the key to the padlock.

That would be me.

Thank you for the information Derek, wow I love this site! I figured about as much, I was just interested in it because we have atotal of FOUR outlets for the entire stage. This was just something to consider adding into next years budget, but renting is also a good option, because our local supply house is within three miles. So, moral of the story is, I could probably rent a distro for a negligible cost, and I'm sure that the rental house has somebody qualified to connect it, because they rent it?
 
That would be me.

Thank you for the information Derek, wow I love this site! I figured about as much, I was just interested in it because we have atotal of FOUR outlets for the entire stage. This was just something to consider adding into next years budget, but renting is also a good option, because our local supply house is within three miles. So, moral of the story is, I could probably rent a distro for a negligible cost, and I'm sure that the rental house has somebody qualified to connect it, because they rent it?

They probably won't drive to your venue and hook it up for you, but they'd probably be able to show you how to perform a tie-in when you pick up the gear at their shop.
 
If it already had cams on the switch then it shouldn't be hard for your electrician to hook up with a little instruction about cam locks and how they go together.
 
The fact that there are two; a 400x3 and a 150x3, sounds like whoever originally did the work had intended that exact use. (Lighting on the 400, stage and sound on the 150.) Depending on the age of the building, you may be able to find a sticker on the equipment and make contact with the original contractor. Sounds like these people knew what they were doing and may be able to let you know what they would suggest. The use of cam's indicates the company had a background in dealing with stage work.
 
...There's your answer. You need to go to whomever controls the key to the padlock. ...
That would be me.
Well; I didn't see that coming! :shock:

In light of the above, some important points [*The following IS NOT a comprehensive list, and reading it DOES NOT make one a Qualified Person.*] about working with Cam-Lok s:
  1. Never make (connect) or break (disconnect) live (when powered).
  2. Always connect in the following order: Grn, Wht, colors (Blk, Red, Blu). Always disconnect in the reverse: colors (Blk, Red, Blu), Wht, Grn.
  3. Unless you can see both ends of the cable (and are certain that it is both ends of the same cable), always treat them as though they are live. Don't go sticking your fingers or anything else in the connector.
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  4. Keep out of reach of children, and the public at large.
  5. Visually inspect the cable and connectors for damage before each use. Any exposed, visible copper or brass is grounds for rejection.
  6. When connecting, line up the flat spot of the male with the nub on the female, insert fully, then turn clockwise as far as possible. It can take quite a lot of force to turn. If the brass insert rotates inside the jacket, do not use the connector.
  7. Keep all downstream switches/breakers OFF, until you have metered the power at the source. Meter every time, no matter how many times you have done it.
 
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Thanks much Derek! Yeah, we don't have an SM or a TD, and so the key for it is just on the general "Stage" ring that we keep locked in the booth, and I'm one of the head techs.

You never know, we could already have a distro stashed away somewhere, and I just need to go find it and either get safety training or find a qualified person. Thanks all of you, I really appreciate the answers; as always, this is the first place I go with a question!
 
Thank you very much, Trevor and Derek, those are EXACTLY what I was thinking of.

Because this is in a school, do you think that going to the school electrician is the right way to go about getting one of these hooked up? (It would only be about three times a year)


If it's only 3 x a year, you'd probably be better off renting than buying. And it would be easier to spend the petty cash per show than to get approval for what is basically a temporary item (in their eyes).
 

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